The energy industry and environmental movement see autonomous vehicles as a dramatic way for altering consumption and emissions. Vehicles that drive themselves and never have accidents can be built much lighter and designed to be more aerodynamic thereby reducing fuel consumption. We haven't even begun to deal with the social mores changes that autonomous vehicles would bring. Would texting and cell phone use restrictions, a.k.a. distracted driving, be relaxed? How about new rules for flirting while driving/traveling? Since the auto companies are determined to provide some of the systems to make driving more appealing and less stressful, we anticipate that over the next five years new vehicles will come equipped with these semi-autonomous driving features, but will allow the driver to choose whether he wants to use them or not, much like Active Park Assist and cruise control. Cars of the future will change and any change that makes them more efficient and safer will ultimately lead to a reduction in gasoline and diesel consumption, not necessarily good for the oil business. Only if these technological improvements encourage increased mileage per driver will it be good news for energy companies.

Eoin Treacy's view Technology is an easy subject to get excited about. As new technologies are invented and the prospect of commercialisation increases the potential for truly life enhancing innovation, productivity gains and associated profits appear to know no bounds. However, the lead time from idea to full scale rollout can often disappoint and one has to question whether outsized valuations are justifiable when prices are accelerating higher. The pace of technological innovation represents an important theme in our medium to long-term bullish outlook but related shares would be best purchased following reversions towards their means.

Google currently trades at an historic P/E of 25.35 and Estimated P/E of 19.19 and remains on an exciting growth trajectory. The share has rallied from the region of the 200-day MA near $750 in late March to test the psychological $900; developing a short-term overbought condition in the process. For as long as momentum lasts, the benefit of the doubt can be given to the upside but the first clear downward dynamic is likely to signal a peak of at least near-term significance and probably the onset of a reversion back towards the mean.

Tesla Motors has attracted a great deal of interest of late with the announcement of its first revenue positive quarter. The company currently trades on an estimated P/E of 558. The share had been trending with a mild upward bias for the last 18 months but exploded out of its range in late March and has since tripled. (Also see Comment of the Day on August 12th 2012). It paused just below $100 yesterday and potential for at least some consolidation of recent impressive gains has increased.

In the online gaming sector Japanese listed Gungho Online Entertainment has an historic P/E of 80 and estimated P/E of 27. In the last four weeks the share has rallied from ¥400,000 to ¥1.6 million. There is little doubt that gaming is experiencing a renaissance following the advent of handheld devices and touch screen hardware. However, the surge in related share prices over the last month represents acceleration and at minimum suggests caution is warranted.

In the 3-D printing sector David highlighted 3-D Systems yesterday which has surged of late. The ExOne Company Inc IPOed in February and the pace of its advance picked up over the last three weeks with a rally of more than 60%. The share trades on an estimated P/E of 373 and remains in a momentum fuelled rally. This is a situation where a trailing stop would be advisable for those with long positions.

Some would argue that P/Es are not that relevant for companies with such incredible growth potential. However, considering the extent to which some have accelerated and the degree to which enthusiasm has propelled valuations, a great deal of good news is already in the price. I am reminded of BYD. The share accelerated from HK$10 in 2008 to a peak six months later near HK$90. It gave up the entire advance in the subsequent bear before building support above HK$10 from 2010. The share has an historic P/E of 761 and Estimated P/E of 56. Prices have also surged of late and the risk of mean reversion has increased. A sustained move below the 200-day MA would be required to question medium-term upside potential.

Social media were last year's cause celebre. A number of high profile shares were listed following a great deal of excitement and hype but Facebook (P/E 1365, Est P/E 40) and Groupon (Est P/E 42) experienced sharp declines as expectations were reined in.

Facebook has stabilised above $25 over the last five months and a sustained move below that level would be required to question potential for some additional support building

Groupon trended lower until November when it found support in the region of $2.60 and has held a progression of higher reaction lows since.

LinkedIn (P/E 544, Est P/E 131) broke successfully above $150 in early February and has been consolidating below $200 for six weeks. A sustained move below the 200-day MA would be required to question medium-term demand dominance.